I'd honestly hope they have a mixture of old and new tech. As shown in the trailer as well as the developers have talked about how Night City will have generations of technology built on top of the last, by the point of 2077.
2077 isn't only going to have tech built that year. Everything will not be brand new and shiny, but also old and gritty. I assume there will be old variations of tech being used even in 2077 as well as newer iterations. Mike Pondsmith him self has said that you'll see this type of design in the game, that shows how technology has evolved over the years from 2020 to 2077 and I think that will show in all areas of the game from the environment to the weapons and gear... everything.
All the different zones of the city and surrounding areas will all have a unique aesthetic and atmosphere, from the slums to the corporate zone to the combat zone.
Also the first buildings to be constructed in Night City are based on older design and would still be standing, and by 2077 would have had more built onto them with new technology.
You can see here that new support beams have been put into place on older buildings to reinforce the structure mass of the new levels built above and also how the design of the buildings at different heights start to change because of the difference in technology used. I've read that was a conscious design choice they wanted to use when making some areas of Night City. They wouldn't just demolish all old buildings just to build a brand new one, not in all cases.
I think the mix of retro tech could still have its presence in the game as well as new generations of tech, and this goes for all aspects of the game. Obviously the game takes place in 2077 but in comparison to todays real world, we still see old tech being used. Vehicles, weapons, clothing, entertainment, as well as city design, all variations of age. I see it working very similarly in the game and to a much greater degree.
Also, using retro tech could have its benefits vs using new tech if its corporate owned, operated and controlled. Could be a underlying theme of the game.